Copper

Copper is a chemical element with symbol Cu (from Latin: cuprum) and atomic number 29. It is a soft, malleable and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a reddish-orange color. It is used as a conductor of heat and electricity, as a building material, and as a constituent of various metal alloys.

Copper is found as a pure metal in nature, and this was the source of the first metal to be used by humans, ca. 8,000 BC; it was the first metal to be smelted from its ore, ca. 5,000 BC; it was the first metal to be cast into a shape in a mold, ca. 4,000 BC; and it was the first metal to be purposefully alloyed with another metal, tin, to create bronze, ca. 3,500.

In the Roman era, copper was principally mined on Cyprus, the origin of the name of the metal from aes сyprium (metal of Cyprus), later corrupted to сuprum, from which the words copper (English), cuivre (French), Koper (Dutch) and Kupfer (German) are all derived. Its compounds are commonly encountered as copper(II) salts, which often impart blue or green colors to minerals such as azurite, malachite and turquoise and have been widely used historically as pigments. Architectural structures built with copper corrode to give green verdigris (or patina). Decorative art prominently features copper, both by itself and in the form of pigments.

Fragile

Fragile may refer to:

Music

Other uses

Autumn

Autumn, interchangeably known as fall in North America, is one of the four temperate seasons. Autumn marks the transition from summer into winter, in September (Northern Hemisphere) or March (Southern Hemisphere), when the arrival of night becomes noticeably earlier and the temperature cools considerably. One of its main features is the shedding of leaves from deciduous trees.

Some cultures regard the autumnal equinox as "mid-autumn", while others with a longer temperature lag treat it as the start of autumn. Meteorologists (and most of the temperate countries in the southern hemisphere) use a definition based on months, with autumn being September, October and November in the northern hemisphere, and March, April and May in the southern hemisphere.

In North America, autumn is usually considered to start with the September equinox and end with the winter solstice (21 or 22 December). Popular culture in North America associates Labor Day, the first Monday in September, as the end of summer and the start of autumn; certain summer traditions, such as wearing white, are discouraged after that date. In North America, the wave of color starts in Canada. It then moves into the United States and across the Great Lakes, and continues down into the mountains of the South. Warm days followed by chilly nights provide the catalyst. In traditional East Asian solar term, autumn starts on or around 8 August and ends on or about 7 November. In Ireland, the autumn months according to the national meteorological service, Met Éireann, are September, October and November. However, according to the Irish Calendar, which is based on ancient Gaelic traditions, autumn lasts throughout the months of August, September and October, or possibly a few days later, depending on tradition. In Australia and New Zealand, autumn officially begins on 1 March and ends on 31 May.